Hi everyone, recently i have been having trouble starting the bike (2013 klx250s with a carb) on the odd occasion when its hot, it doesnt do this often but when it does, it will not start for a good few cranks.
When i bought the bike with 5,900kms it never did anything like this, and has very, very slowly started to have trouble starting while hot on occasion.
I had just taken it for a ride today and it died on me for the first time while stopped at an intersection (no, i did not stall XD) and it took a good few cranks before firing up again and ran like nothing happened.

As the bike sits now, just ticked over 11,000kms with plans to do the valves very soon. Could this be part of the cause?
I also used to run 98 octane, untill i found out that the 98 octane in my country contains ethanol. Ive heard ethanol and carbs dont mix.

Has anyone else here had some similar issues? Any ideas?
I will add that i dont have any preformance mods like an exaust, airbox, and carb tune. Bike is stock in that department.

Thanks all, Sam.

 

What country? It helps if people at least know what country you are in, maybe include the state or province. That information helps people know if they have information that can help you.

Virtually all stock carbed KLX250s are lean jetted, which can cause issues with starting. I know my 2009 would crank for a lengthy time to start and worse when warm, with around 20,000 km on it, After I did the jetting as shown in the hop up link in my signature, the bike started up near instantly in most all conditions, Ran better too. There are two avenues to go with jetting, I did the jetting using parts from Kawasaki for the Kiehin carb. Others have done the DynoJet kits. My brother and I found the jetting we used was pretty much plug and play, being at around 1000 ft elevation, I recommend it highly.

I do know if the valves are tight you might have one that isn't quite sealing. I'd do the valves for sure, then while doing them, check the carb and see if it has been jetted. One thing that might indicate it is if the snorkel used on the bike is the small stock one or the bigger KDX snorkel. The KDX snorkel is twice the cross sectional size for better breathing and would likely be done if the jetting was done. It's worth looking into for sure. Bike starts quicker and easier in all weather. Just understand how elevation may require a bit smaller pilot and main jet.

The information in my document came from D. Pippin's KLX250 page, he has a lot of good information there. I copied some of it to provide a second source and recommend others do the same to keep the information out on the web. Click here for Pippin's page

 

I'd check to see if the carb bowl was having trouble keeping full. A clogged fuel filter could slow the flow enough to empty the bowl enough to stall when you stop immediately after running at speed.

 

Thanks for the info. I live in New Zealand (small island close to Australia), I live and ride at sea level. My airbox has the stock snorkel, i am pretty sure the carb hasn't been messed with but i cannot tell for sure.
Cheers

 

Good idea, may I ask where is the fuel filter? I just had a look and my fuel hose runs straight from the tank to the petcok, and then to the carb.

Cheers for the info